I presume you need to solve

There are a couple of ways to do this, but I suspect you are looking for the use of the quadratic formula.

Given then

So for , a = 2, b = 3, c = -3. Thus:

For the other problem:

I don't know what you mean by "make x the subject." I am guessing you mean solve in terms of x?

This is a quadratic in terms of b. So using the quadratic formula again:

-Dan